Comparison of seed conditioning procedures for Eucalyptus grandis W.!Hill ex Maiden using seed sizing, specific gravity table and general blower

Eucalyptus grandis seed cleaning is particularly difficult due to the small size of the seeds. When large seed quantities are involved. the usual method of screening followed with an air blower is too time consuming resulting in inefficiencies and bottlenecks in the process. Different seed cleaning processes are analyzed to evaluate their effectiveness in removing the chaff from the seeds. The combination of seed sizing with the specific gravity table gives the best results, averaging a 47.3% increase in the number of germinants. Although screening before the specific gravity table gives better results, with an 20.4% increase in the number of germinants. it is not significantly different from using the specific gravity table before screening. Germination was higher with screening after gravity table than with the gravity table alone at both the upper and lower positions of the deck.